Display User's SID

[guayo]

The following code displays the selected SID's number.

In my case S-1-5-21-1123561954-2054111206-734534423-1009

Private Declare Function ConvertSidToStringSid Lib "ADVAPI32.dll" Alias "ConvertSidToStringSidA" (ByVal Sid As String, ByRef lpStringSid As Long) As Long
Private Declare Function IsValidSid Lib "ADVAPI32.dll" (ByRef pSid As Any) As Long
Private Declare Function LookupAccountName Lib "ADVAPI32.dll" Alias "LookupAccountNameA" (ByVal lpSystemName As String, ByVal lpAccountName As String, ByVal Sid As String, ByRef cbSid As Long, ByVal ReferencedDomainName As String, ByRef cbReferencedDomainName As Long, ByRef peUse As Long) As Long
Private Declare Sub CopyMemory Lib "kernel32.dll" Alias "RtlMoveMemory" (ByRef Destination As Any, ByRef Source As Any, ByVal Length As Long)
Private Declare Function GlobalFree Lib "kernel32.dll" (ByVal hMem As Long) As Long
Private Declare Function LocalAlloc Lib "kernel32.dll" (ByVal wFlags As Long, ByVal wBytes As Long) As Long
Private Declare Function LocalFree Lib "kernel32.dll" (ByVal hMem As Long) As Long
 
Private Sub Command1_Click()
 
UserSID = GetSid(Text1.Text & "\" & Text2.Text)
 
Text3.Text = UserSID
End Sub
 
 
Private Function GetSid(accountName As String) As String
 
Dim userName As String
Dim UserNameSize As Long
Dim Sid As String
Dim SidSize As Long
Dim Domain As String
Dim DomainSize As Long
Dim snu As Long
Dim sReturn As String
 
userName = String$(255, 0&)
Sid = String$(255, 0&)
Domain = String$(255, 0&)
sReturn = String$(255, 0&)
 
UserNameSize = 255
SidSize = 255
DomainSize = 255
 
Call LookupAccountName(vbNullString, accountName, Sid, SidSize, Domain, DomainSize, snu)
If IsValidSid(ByVal Sid) = 0& Then Exit Function
 
Call ConvertSidToStringSid(Sid, snu)
Call CopyMemory(ByVal sReturn, ByVal snu, 255)
 
sReturn = Left$(sReturn, InStr(vbNull, sReturn, vbNullChar, vbBinaryCompare) - vbNull)
Call GlobalFree(snu)
 
GetSid = sReturn
End Function

My question is. Why doesn't the number I get match with any of my HKEY_USERS ?

S-1-5-18
S-1-5-19
S-1-5-20

Thank you